Lower voltage modules - do you try to recondition these or just replace?

Might as well try to revive them by doing multiple discharge / charge cycles. Sometimes they might go back to useable but not likely. In theory discharging to a low voltage might help. So you can start with 6 volt minimum discharge voltage on a hobby charger. Then see the amp hours the module accepts during a charge to full. If no improvement, keep dropping the lower discharge voltages and check for any improvement in amp hour capacity. I reconditioned a pack and noted the worst 5 modules in terms of amperage capacity and replaced with other used modules that had higher amp capacity. Once the bad modules were replaced, then used internal resistance measurements to pair up the modules so each pair had approximately the same total internal resistance. Then did a balance charge for 24 hours.

 

Second the above....
You got nothing to lose by trying a few charge/discharge routines on modules showing lower capacities.
If they test good, you can use them.....but don't skimp, either on the reconditioning or the testing.
My modules have lasted over 6 years now.
Do full top offs between each, with discharges between each down to 50% voltage, then down to 25%, then lastly to less than a volt.
Finish off with a nice long topping off again. Then test the hell out of it. I did three complete repetitions of the above.
Adding brand new full strength blades into a pack of weaker ones can bring in it's own problems.
One note - the amount the thing accepts during the charging phase isn't as important as the amount it can discharge, focus on the latter.

 

I used a ProTek R/C "Prodigy 610 QUAD AC" LiHV/LiPo/LiFe/NiMH AC/DC Battery Charger. There's a lot of settings and options in the menu so you can customize it to your needs. It did a good job reconditioning the modules. It didn't come with the cables, so ended up buying the connectors I needed and building them with wires.

 

Not likely indeed.

Trying to "recondition" worn out batteries is an exercise in futility, no matter what technique you use.

Most everybody who tries it eventually comes to that conclusion.

 

Some people think that getting the voltage of the battery back up - the battery is good. That's far from the truth. If the battery can't handle an electrical load, it's useless. It's the same as a 12 VDC car battery that reads 12 VDC on a meter but can't start a car. How does it help the other batteries in you pack drive the electric motors in your transmission?

Just my 2 cents....

 

Reconditioning is definitely worth it. If the Prius is being driven constantly, and not just sitting around for months on end without being started, then there will likely be only one bad module in the pack. The battery ECU will immediately detect the bad module which has a lower voltage than the rest. So, if that one bad module is quickly isolated and removed from the pack, the reconditioned pack will serve a long useful life. It just makes sense not to scrap a whole battery pack due to one bad module.

 

The experience of MANY users......and the opinion of actual battery experts......is in direct opposition to everything you just said.

IF.....you wait until one of more cells is really BAD, it is too late for any useful "reconditioning".